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991.
Zal U’yun Wan Mahmood Nik Azlin Nik Ariffin Abdul Kadir Ishak Norfaizal Mohamed Mei Wo Yii Kamaruzaman Ishak Zainab Pa’wan 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):901-906
A method is described for the determination of 90Sr in environmental samples using combination of developed in-house method, Eichrom Sr resin and Beta Counter. Strontium was
efficiently, rapidly and simply separated from Ca and other interfering matrix components by Eichrom Sr resin. All the results
in general showed good accuracy, high precision, reliable and in good agreement between these two measured and certified value
of SRM (i.e. IAEA-375, IAEA-326, IAEA-152 and IAEA-414). As a whole, the procedure described in this work notably improves
conventional methods in particular concerning the time needed, sample volume, safer and others. Thus, the introduced method
was successfully performed and will be applied to actual sample for the determination of 90Sr in different environmental materials such as soil, sediments, milk, biological sample, water etc. 相似文献
992.
研究了广义Ekeland变分原理在拟度量空间中的一些重要应用.利用广义Ekeland变分原理证明了函数f满足关于α的Takahashi ε-条件当且仅当f满足关于相同α的Hamel ε-条件.此外,利用关于α的Takahashi ε-条件得到了一些重要结论. 相似文献
993.
We study the structure of a metric n-Lie algebra G over the complex field C. Let G = SR be the Levi decomposition, where R is the radical of G and S is a strong semisimple subalgebra of G. Denote by m(G) the number of all minimal ideals of an indecomposable metric n-Lie algebra and R ⊥ the orthogonal complement of R. We obtain the following results. As S-modules, R ⊥ is isomorphic to the dual module of G/R. The dimension of the vector space spanned by all nondegenerate invariant symmetric bilinear forms on G is equal to that of the vector space of certain linear transformations on G; this dimension is greater than or equal to m(G) + 1. The centralizer of R in G is equal to the sum of all minimal ideals; it is the direct sum of R ⊥ and the center of G. Finally, G has no strong semisimple ideals if and only if R⊥■R. 相似文献
994.
In this paper, we establish a general solution and the generalized Hyers-Ulam-Rassias stability of the following general mixed
additive-cubic functional equation
f(kx + y) + f(kx - y) = kf(x + y) + kf(x - y) + 2f(kx) - 2kf(x)f(kx + y) + f(kx - y) = kf(x + y) + kf(x - y) + 2f(kx) - 2kf(x) 相似文献
995.
This paper investigates ultimate boundedness and a weak attractor for stochastic Hopfield neural networks (HNN) with time-varying delays. By employing the Lyapunov method and the matrix technique, some novel results and criteria on ultimate boundedness and an attractor for stochastic HNN with time-varying delays are derived. Finally, a numerical example is given to illustrate the correctness and effectiveness of our theoretical results. 相似文献
996.
Jacobs PG Konrad-Martin D McMillan GP McDermott D Fausti SA Kagen D Wan EA 《The Journal of the Acoustical Society of America》2012,131(2):1296-1306
Stimulus-frequency (SF) otoacoustic emission (OAE) amplitude and the amplitude of medial olivocochlear (MOC) inhibition of SF OAEs for ipsilateral, contralateral and bilateral MOC reflex elicitors were recorded in six subjects with type 2 diabetes during a glucose tolerance test (GTT). Five of the six subjects were tested twice for a total of 11 trials and three subjects were tested in a control experiment. During the GTT experiment, the subjects' blood glucose was elevated from a euglycemic level below 150 mg/dL to a hyperglycemic level above 160 mg/dL following the consumption of a bolus of 80 g of sugar. A subset of three subjects were tested in a control experiment during which SF OAE and MOC reflex measurements were made while blood sugar levels remained constant within the euglycemic region. Mean SF OAE amplitudes were elevated following glucose consumption. A statistically significant increase in MOC inhibition amplitude was observed during elevated sugar levels for the 11 GTT trials. Maximum inhibition occurred about an hour after glucose consumption when blood glucose levels peaked. Results indicate that acute hyperglycemia influences efferent control of the cochlea in people with type 2 diabetes. 相似文献
997.
A density-functional theory investigation on desorption of O2 on Sn(111) and its comparison with initial oxidation on the X(111) (X=Si,Ge, Sn,Pb) surfaces
![]() <正>The first-principles calculations are performed to investigate the adsorption of O2 molecules on an Sn(111) 2×2 surface.The chemisorbed adsorption precursor states for O2 are identified to be along the parallel and vertical channels, and the surface reconstructions of Sn(lll) induced by oxygen adsorption are studied.Based on this,the adsorption behaviours of O2 on X(111)(X=Si,Ge,Sn,Pb) surfaces are analysed,and the most stable adsorption channels of O2 on X(111)(X=Si,Ge,Sn,Pb) are identified.The surface reconstructions and electron distributions along the most stable adsorption channels are discussed and compared.The results show that the O2 adsorption ability declines gradually and the amount of charge transferred decreases with the enhancement of metallicity. 相似文献
998.
This paper studies the dynamic stress intensity factor (DSIF) at the interface in an adhesive joint under shear loading. Material damage is considered. By introducing the dislocation density function and using the integral transform, the problem is reduced to algebraic equations and can be solved with the collocation dots method in the Laplace domain. Time response of DSIF is calculated with the inverse Laplace integral transform. The results show that the mode Ⅱ DSIF increases with the shear relaxation parameter, shear module and Poisson ratio, while decreases with the swell relaxation parameter. Damage shielding only occurs at the initial stage of crack propagation. The singular index of crack tip is -0.5 and independent on the material parameters, damage conditions of materials, and time. The oscillatory index is controlled by viscoelastic material parameters. 相似文献
999.
在将相关正态变量转换成独立正态变量的基础上,首先建立了基于Monte Carlo模拟的相关正态变量可靠性灵敏度分析的转换法,并对其可靠性灵敏度估计值作了方差分析.其次将Monte Carlo转换法与自适应超球重要抽样法相结合,建立了相关正态变量可靠性灵敏度分析的自适应超球重要抽样转换法.所建立方法利用抽样样本提供的信息,通过迭代逐步确定最优超球半径,极大地提高了算法的稳健性和效率.由于自适应超球重要抽样转换法融合了Monte Carlo法的普适稳健性和超球重要抽样的高效性,因此它对于高度非线性隐式极限状态方程、多个失效模式串、并及混联系统、多个最可能失效点问题均具有很强的适应性,算例结果充分证明了这些优点. 相似文献
1000.
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